Microbial elements exist in virtually every food manufacturing operation. The microbial elements (e.g., bacteria) are dynamic living organisms that are affected by their environment and in turn affect the environment in which they live. Bio-processes and other processes, such as food manufacturing, are affected both positively and negatively by the state of bacteria, molds, fungi, algae, and other bio-species and bio-chemical reactions. The techniques typically used to determine the level of bacteria can take days to perform (e.g., before the results from a laboratory test can be conducted and the results obtained). Often, processes are operated in an extremely conservative and inefficient manner to help insure low levels of bacteria. Occasionally, processes may be inadvertently operating with high bacteria levels due to inadequate or outdated information on bacteria present. For example, some processes may not have sensors to indicate the bacteria level. In other cases, the time from when a sample was extracted from the lab and the biological state determined may be excessive such that the laboratory test results do not reflect the current state of the production process. Further, products may need to be scrapped due to observed or suspected high bacteria levels.
A technique typically used to determine the level of bacteria in a process is to obtain a sample of the material from the process and place the sample in (or on) a nutrient under controlled conditions to permit any bio-agents present to grow and multiply (i.e., culture a sample from the production line). When organisms present in the culture dish have had sufficient time to grow and multiply, the organisms are visually and/or chemically inspected to determine the species and the quantity present. This process typically takes one or more days before the bacteria types and levels can be determined. The time necessary to determine micro-biological information is inadequate for feedback control of the process and is generally inadequate to permit changes in process set-points or for production scheduling. In addition, products often cannot be shipped until the bio-assay is completed with satisfactory results. Some other techniques (such as Polymerase Chain Reaction (PCR) and real-time PCR) can reduce the time to hours using laboratory techniques. Other techniques, such as optical methods (e.g., spectroscopic) are costly and have limited use. Further techniques include electro-chemical sensors that are able to provide real-time or near real-time bacteria assessment.
The control implications of such delays (or due to an unknown level of bacteria) might be that processes are run excessively conservative (e.g., high temperatures, colder temperatures, longer cooking time, higher retort temperatures, frequent washdowns, anti-microbials added, and so forth) to insure low bacterial levels. Periodically product samples may be taken and analyzed in the laboratory to help insure the process keeps the bacteria below threshold levels. It can also be very difficult to change an established or approved manufacturing process for food and pharmaceutical products. A lengthy procedure is often needed to establish the validity and biological safety of a modified process.